1) We are continuing our work on exosomes as a source of biomarkers, including proteins and miRNA. We are exploring proper normalizing techniques for these biomarkers, including counting exosomes by Nanosight Tracking Analysis and measuring TSG101 by western blot. 2) We are continuing a public-private consortium with the HESI Genomics microRNA Focus Group to compare standard protocol vs site-specific protocols from multiple sites; variations will identify which preanalytical steps affect microRNA detection and quantification in biofluids in drug-induced injury models. The initial model is a cardiotoxin that stimulates release of miRNAs into the circulation, which will shed light on renal handling of miRNA. Urinary miRNA from non-renal sources is expected to be non-exosomal.